1. Field of the Invention
This invention relates to a flat cable connecting device which is suitable for connecting an end of a flat cable, which extends through a slit formed in a partition wall to connector pins.
2. Description of the Prior Art
A flat cable is used, for example, for connection between a rotary transformer located within a cylinder of a rotary head mechanism of a video tape recorder and connector pins located outside the cylinder. Conventionally, a slit is formed in a partition wall of the cylinder so as to allow the flat cable to extend therethrough.
However, in a flat cable connecting device as described above, if the slit formed in a circumferential wall of the cylinder is large, dust may readily enter the inside of the cylinder. Further a large slit is undesirable because it reduces the strength of the cylinder. Therefore, it is required to minimize the size of the slit. Meanwhile, the connector pins are disposed in a spaced relationship by a predetermined fixed distance on a printed circuit board which is integral with a connector body. Because it is necessary to assure a distance for insulation between each adjacent pins, and the diameter of the pins cannot be reduced below a particular limit, if the number of the pins is increased, the width of the connecting end of the flat cable must be increased accordingly. As a result, the size of the slit formed in the cylinder must be increased so as to allow the connecting end of the flat cable to pass therethrough. It is also a problem that it is difficult to pass the flat cable through the slit.
FIG. 2 shows a conventional flat cable connecting device having the disadvantages as described above. Referring to FIG. 2, a flat cable 25 has a plurality of printed wires 26 formed thereon and a plurality of small holes 28 formed through the printed wires 26 at an end thereof for receiving therein connector pins 24 securely mounted on a printed circuit board 23 to establish mechanical and electrical connection between the flat cable 25 and the printed circuit board 23. The small holes 28 are arranged in a row extending in a direction perpendicular to a longitudinal axis of the flat cable 25. Accordingly, the end of the flat cable 25 at which the small holes 28 are formed must be widened relative to the body portion of the flat cable 25, as seen in FIG. 2. The flat cable 25 extends through a slit 31 formed in a partition wall 21 such as a circumferential wall of a cylinder of a rotary head mechanism of a video tape recorder. Thus, in connecting the flat cable 25 to the printed circuit board 23, the widened connecting end of the flat cable 25 must be passed through the slit 31, for example, in a manner as shown in phantom in FIG. 2.
A flat cable connecting device as shown in FIG. 3 is also known. In the arrangement of FIG. 3, small holes 28 at a connecting end of a flat cable 25 for receiving therein connector pins 24 on a printed circuit board 23 are arranged in a row extending in a direction parallel to the longitudinal axis of the cable 25. The flat cable 25 is also widened at its connecting end as seen in FIG. 3. Accordingly, a slit 31 formed in a partition wall 21 has a sufficient width to allow the widened connecting end of the flat cable 25 to pass therethrough.
Where the arrangement of FIG. 3 is employed, the connector must be arranged in a vertical direction as seen in FIG. 4. Consequently, the connector and the printed circuit board extend to a position in which they cover part of an outer periphery of a rotary cylinder 32. Accordingly, there is the possibility that a tape may contact the connector or the printed circuit board, and hence the arrangement is not preferable for the application.